263—86 INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
tootli in G. lupus, is of precisely tlie same length as m. 1 ; the length of the latter 
being much smaller than that of the same tooth in any individuals of the living 
species having an upper carnassial of the same size. The larger individuals of 
C. lupus make the closest approach in this respect to the fossil, but even in the 
nearest of those m. 1 is decidedly longer than pm. 4 . The fossil also differs from all 
the living species, except G. laniger, in having the * united length of m. 1 and m. 2 
either equal to, or less than that of pm. 4 . The first upper true molar of the fossil 
differs from the corresponding tooth of C. lupus , in having the outer lobes, and 
especially the hinder one, less completely conical; being distinctly compressed 
laterally : the outer cingulum is also more developed. In these respects the tooth of 
the fossil resembles the corresponding tooth of the jackal. 
On the whole, apart from the question whether the living Old World wolves 
should be referred to one or more species, it appears probable that the 
differences in the form of the angular process of the mandible, and the above- 
mentioned relations of the carnassial teeth, indicate the specific distinctness of the 
Siwalik wolf from any of its existing Old World congeners. Seeing that in the 
meionocreodont alopecoids m. i is always longer than pm. 4 , it would seem that in 
cases where these two teeth are equal in length the degree of specialization is the 
greatest, and it may, therefore, be concluded that the Siwalik wolf was probably a 
more specialized animal than any of the existing species; certain individuals 
of C. lupus coming nearest in this respect. The equality in the length of pm. 4 and the 
united length of m. 1 and m. 2 is also indicative of a high degree of specialization in 
the Siwalik wolf. There are not wanting, as will be noticed below, other instances 
where Siwalik carnivores are more specialized than their existing allies ; and if the 
above conclusions be true it would seem doubtful whether the Siwalik wolf can have 
been the direct ancestor of any of the living forms : this is perhaps confirmed by the 
marked discrepancy in the proportions of its carnassial teeth to those of the existing 
Indian wolf. 
Among the existing wolves, or thooids, of America, according to Prof. Huxley’s 
measurements, 1 the only species which has carnassial teeth at all approaching in size 
those of the Siwalik fossil is the North American C. occidentalis : in that species, 
however, pm. 4 is always shorter than m. 1. In the peculiar S. African Lycaon pm. 4 is 
considerably shorter than m. 1, and the corresponding tooth of the fossil. All species 
of Cyan are distinguished from the fossil by the absence of m. 3 ; while Lu corns is 
distinguished by the absence of pm. 1. In the pliocene of Italy there occurs Cams 
etruscus , Forsyth-Major ; 2 a wolf distinguished from existing species .by the larger 
size of the talon of m. 1, and the greater development of the cusps of the same part : 
those cusps frequently attaining nearly the same height as the anterior lobe of the 
blade. The inner cusp of the blade is also larger and more detached. The general 
form of the mandible is nearer that of the wolf than that of the Siwalik fossil ; and 
m. 1 has its outer lobes of the conical form of those of the former. Ganis falconeri , of 
i Op. cit., pp. 267, 271. 2 < Atii. Soc. Tosc. Sci. Nat.,’ vol. III., p. 208, pis. XIII. -IV. 
